Remove GID/ID coercions, but not compatibility

What does this MR do and why?

See #257883 (closed)

This splits up the removal of GID/ID compatibility by only removing the coercions, leaving the functionality to be removed in !83457 (merged).

We keep the coercions for Query.milestone and Query.iteration, since these are needed for the burnup chart.

After this is merged, queries that use the ID type will pass validation on the server, but cause 500 Internal Server Errors when executed. These queries should all fail local validation with any spec compliant validator that has access to our schema.

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